Geomagnetic cutoff of cosmic rays during the March 23–24, 2023 magnetic storm: Relationship with solar wind parameters and geomagnetic activity taking into account latitudinal effects

In this paper, we calculate geomagnetic cutoff rigidities during the strong magnetic storm of March 23–24, 2023, using 1) the spectrographic global survey method based on observational data from cosmic ray recording by the global network of stations (Rsgs); 2) numerical trajectory calculations in a model magnetic field of the magnetosphere (Reff). The geomagnetic cutoff rigidity has been determined for nine cosmic ray stations at different latitudes. We calculated the correlations of the variations in the geomagnetic cutoff rigidity ΔRsgs and ΔReff with magnetic and dynamic solar wind parameters and the geomagnetic activity indices Dst and Kp. It has been found that the geomagnetic cutoff rigidity calculated by both methods correlate most strongly with Dst and the electromagnetic parameters of the solar wind. No significant correlation with the dynamic parameters was observed. The analysis has shown that the response of ΔRsgs to the controlling magnetic parameters and Dst changes with latitude of the observation station: the correlation reaches its highest values at midlatitudes and drops significantly toward the equator. The correlations of ΔReff calculated by the model do not reveal a latitudinal dependence.